RESUMEN
OBJECTIVE: The purpose of this work was to investigate the synthesis of T3 receptors in human tumors of the anterior pituitary gland, its relationship with the hormone synthesized and/or secreted by the tumor and the post-surgical evolution of the patient. METHODS: Patients were evaluated clinically and by magnetic nuclear resonance to classify the adenoma according to their size. Hormonal concentrations in sera were determined by radioimmunoassay. Immunohistochemistry of the pituitary hormones was performed in the tumors. Tumors were obtained at surgery and immediately frozen in ice, transported to the laboratory and stored at -70 degrees C. Reverse transcription was performed with purified RNA from the tumors. RESULTS: Out of 33 pituitary tumors, 29 had RNA for T3 receptors synthesis (88%). They were present in different histological specimens, the tumors were grades 1-4 according to their size, and there was no relationship between the size of the tumor and the presence of T3 receptor RNAs. The post-surgical evolution of the patient was mostly dependent on the size and not on the presence of T3 receptors. DISCUSSION: The presence of thyroid hormone receptors in pituitary tumors is in line with two important characteristics of these tumors: they are histologically benign and well differentiated.
Asunto(s)
Adenoma/metabolismo , Biomarcadores de Tumor/genética , Neoplasias Hipofisarias/metabolismo , Receptores de Hormona Tiroidea/genética , Adenoma/genética , Adenoma/patología , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Humanos , Masculino , Neoplasias Hipofisarias/genética , Neoplasias Hipofisarias/patología , Valor Predictivo de las Pruebas , Pronóstico , ARN Mensajero/análisis , ARN Mensajero/metabolismo , Radioinmunoensayo , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Sensibilidad y Especificidad , Tiroxina/metabolismoRESUMEN
BACKGROUND: We have postulated that metabolic oxidation could be the source of signs and symptoms of hyperthyroidism. The present study was designed to evaluate urinary malondialdehyde levels in Graves' disease and compare this oxidative stress biomarker with the clinical evolution of patients suffering this illness. METHODS: We evaluated the concentration of urinary and serum malondialdehyde (MDA) in 36 patients with Graves' disease. Patients were treated with the antithyroid drug methimazole (MMI; Group A) or antioxidant mixture (200 mg vitamin E, 3 mg beta-carotene, 250 mg vitamin C, 1 mg Cu, 7.5 mg Zn, 1.5 mg Mn, and 15 microg Se; Group B). RESULTS: MDA concentrations were higher in hyperthyroid patients compared to euthyroid controls, and a positive correlation was observed between serum and urinary MDA levels. Group A decreased urinary MDA to control values. There was a positive correlation between the clinical score and the heart rate of patients with urinary MDA before and during the treatment with MMI (Group A). Similar results were observed after treatment with the antioxidant mixture. CONCLUSIONS: Urinary MDA might be a good parameter in the follow-up of patients during MMI treatment. We proposed that oxidative stress correlates with signs and symptoms of hyperthyroidism.